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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Towards Educating Artificial Neural Systems</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Simon Colton</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Original “Yellow</institution>
          ,
          <addr-line>Red, Blue” by Wassily Kandinsky</addr-line>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>School of Electronic Engineering and Computer Science, Queen Mary University</institution>
          ,
          <addr-line>London</addr-line>
          ,
          <country country="UK">UK</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>SensiLab, Faculty of Information Technology, Monash University</institution>
          ,
          <country country="AU">Australia</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>In the context of text-to-image generators, we discuss how a neural system could be enhanced to follow a knowledge base expressing certain moral considerations, in order to address some looming concerns. We also propose self-educating procedures that enable the system to produce rule-based approximations of its functioning, and illustrate this with an application to the creative interpretation of images.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;Pre-trained Neural Models</kwd>
        <kwd>Text-to-image Generation</kwd>
        <kwd>Computational Creativity</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        Until relatively recently, neural image generators were developed for largely utilitarian purposes,
for instance BigGAN [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] was trained to generate novel images in 1 of 1,000 classes such as
hamburgers or terriers. Moreover, the engineers of such systems would lament issues such as
class leakage where an image looks like it is from two classes, e.g., an image of a tennis ball that
looks like a yellow bird. Text-to-image generators [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] were likewise used largely to generate
images which could exist in reality, such as “a red bird in a tree”.
      </p>
      <p>
        Over the last 18 months, the situation has dramatically changed and one of the main usage
of neural image generators is currently to produce highly imaginative images which could
never exist in reality. Huge neural models with billions of nodes and training costs in the
millions of dollars from OpenAI, Google and others have been produced which can, on demand,
generate images quickly with high fidelity to a given text prompt, no matter how outlandish
and imaginative the prompt is. As examples, figures 1(a) and 1(b) portray generated images
from the DALL-E 2 (OpenAI) [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] and Imagen (Google) [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] approaches, which currently produce
the highest-quality images in terms of fidelity to the prompt and coherence.
      </p>
      <p>
        In [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ], we predicted that generative search engines will soon revolutionize the creative
industries, where text-to-image generators like Imagen and DALL-E 2 will be used much like
Google image search currently is, i.e., with images being constructed, rather than retrieved, to
ift a search term. This prediction is still sound, but there are, however, hurdles to overcome in
making such generative processes available to the public. Access to both DALL-E 2 and Imagen
was initially restricted, and there are limitations on the usage, e.g., users are not allowed to
share images from DALL-E 2 that portray realistic faces. This has led to some users being asked
to remove generated images from social media platforms.
      </p>
      <p>We look here at a particular problem with text-to-image generation, namely the lack of
diversity in the images generated due to biases trained into the neural models at the heart of
the systems. We explore the position that large models trained on internet-sized datasets of
images/text provide breakthrough opportunities for content generation, but should be guided
by rule-based systems in a neurosymbolic approach. We propose a straightforward way in
which a system employing a neural generator could be further educated (rather than merely
trained on data), with rules representing moral positions which may directly contradict the
training data. We also suggest how symbolic knowledge can be extracted from such models to
highlight biases and semantic connections. To illustrate the benefits of this, we present some
results from an application to the creative interpretation of images.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Guiding Image Generation with Moralbases</title>
      <p>When asked to generate multiple images for the prompt “a builder”, DALL-E 2 produces pictures
of men only, as per figure 1(c). This is because the models DALL-E 2 employs have been trained
on millions of image/text pairs where the overwhelming majority of faces associated with the
word “builder” are male. If asked to do the same, many, if not most, young children would draw
ifve men in a row if asked to portray five builders. Starting from TV characters such as Bob the
Builder, through every trip past a building site and all but the most inclusive of books, builders
are – in the experience of children – overwhelmingly male in nature. In the terminology of
machine learning, children are trained with a bias towards portraying builders as male.</p>
      <p>While it may be disappointing to progressive parents or teachers that a child expresses lack
of diversity when portraying certain professions such as builders, this ofers an opportunity
to educate children with a more general lesson which may expressly contradict the evidence
of their own experience. In particular, parents can tell a child that a person of any gender can
be a builder, and/or they may ofer a more general lesson that, in principle, a person from any
background can do any job (perhaps with additional training). In future, if a child so educated
is asked to draw a builder, they may recall this lesson and draw a female builder from their
imagination rather than their experience.</p>
      <p>
        A purely deep-learning approach to address biases baked into large neural models would be
to curate and balance the training data e.g., to make sure there are an equal number of male
and female builders represented. While this might be feasible for training a generative model
such as a GAN [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] specifically for producing images of a certain type, it would be impossible
to balance the data required for a general-purpose text-to-image generator where the subject
material could reflect any aspect of human life, real or imagined. For instance, for builders
alone, thousands of images of every type of human varying over gender, ethnicity, (dis)ability,
age, etc. would be needed to ensure that images are generated in an inclusive way.
      </p>
      <p>Scraping internet-scale datasets for training is very convenient, and it is already
dificult/impossible for organisations to remove ofensive images from the training set; it seems
highly implausible to imagine attempting to balance training data for large models. Moreover,
this would miss one of the big advantages of text-to-image generators, namely that they can
be directed to produce images that are not representative of their training data. That is, while
DALL-E 2 and Imagen may by default produce a white, male face in a yellow builder’s hat when
prompted with “a builder”, when prompted instead with “a female builder”, this would override
the default and deliver an image of a woman dressed as a builder. A position we take is that
the pre-trained neural models in text-to-image generators are equivalent to naïve children who
have generalised from what’s around them, but who need to be educated with higher-level rules
which may contradict their experience. That is, rather than blaming the neural model, the data
or the training regime for the inherent bias that it can be used to portray, we should blame (and
ifx) the processes surrounding the employment of the neural model for the bias.</p>
      <p>
        We propose that neural systems employing pre-trained large image/text models for image
generation should be guided by what could be called a moralbase of high-level rules. In particular,
these rules could be employed for automated prompt engineering [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ], whereby a user’s prompt
is altered before it is passed to the generative engine. One can imagine a simple approach where
certain abusive words are removed from prompts, changed to non-ofensive versions, or where
the system refuses to process any prompt with such words in, as is our approach for the @artbhot
text-to-image Twitter bot [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. To begin to address lack of diversity in image generation, we can
imagine that a moralbase could encode rules such as () → () ∨ () ∨
(). Alternatively, we could express rules at a higher level, for example as follows:
_() ∧ _ ( ) ∧ ℎ_ (,  ) → ℎ_(, )
ℎ_(, ) → () ∨  () ∨ ()
_ ()
Another alternative would be to use a formalism such as stochastic logic programming [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] to
represent moral considerations probabilistically. The process could then derive a set of re-write
rules so that prompts can be engineered on a rotating basis to increase the diversity of outputs.
For instance, in one run, “builder” could be replaced by “male builder” and in another by “female
builder”. Complex natural language processing and re-writing of prompts may be needed for
this, but we have found that simply appending a word like “man” or “woman” to a prompt can
lead to images portraying the gender required.
      </p>
      <p>In the same way that it is not feasible to balance data and retrain a neural model to remove
biases, it is not feasible to imagine a prompt engineering scheme which can handle all biases
which may present. Hence, we expect that moralbases will be highly focused and probably
specific to a particular user, organisation, project, political leaning, etc., and that individual
users could build up multiple moralbases to switch between. We also expect that automated
reasoning, constraint solving, planning and other classical AI techniques will be required for
moralbases to be used to their full potential, and we are currently experimenting to this efect.</p>
    </sec>
    <sec id="sec-3">
      <title>3. Extracting Semantic Knowledge from Neural Models</title>
      <p>
        The building up and deployment of moralbases could be time consuming and dificult, and some
automation may improve matters by identifying biases and relationships in the pre-trained model
that the moralbase guides. To make initial proposals for this, we have recently experimented
with an implementation of CLIP-VQGAN which can perform text-to-image generation, as
described in [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]. Here, latent vector inputs for VQGAN are found using gradient descent, in
such a way that the image reflects a given text prompt. CLIP [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ] comprises two models for
encoding images and text respectively into the same latent space, so pairs of images and text
(,  ) are encoded to vectors with a smaller cosine distance between them if  reflects  than
if  has no relation to  . The loss function for the gradient descent is based on the average
cosine distance between CLIP encodings of subimages of the VQGAN-generated images and the
CLIP encoding of a given text prompt. This works in a similar way to CLIP-Guided BigGAN [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ].
CLIP has encoded a vast amount of visual and textual information, and we can mine semantic
relationships it has learned. For instance, given a list of colours, it is straightforward to get
CLIP to identify that the word “chocolate” has the smallest cosine distance to “brown”, “sun” is
closest to “yellow”, etc. Such relationships can be extracted as symbolic knowledge to aid in
constructing a moralbase, and can be seen as self-education of a pre-trained neural model.
      </p>
      <p>
        As an artistic application of this kind of semantic extraction, we generated some creative
interpretations of images. To do this, we implemented a process which finds both nouns and
adjectives closest (in terms of cosine distance of CLIP encodings) to an image, then (as above),
we extract CLIP relationships between the adjectives and nouns to produce sentences which
caption the image. Given an image and a caption, CLIP-VQGAN can generate a novel image
which reflects both the original image and the caption. We used this functionality to produce
a series of creative interpretations given in the appendix. As an example, the system has
interpreted/captioned the first original image in the appendix as a “worn and forsaken ruin” and
produced a new image accordingly, which also references strongly the original. Social media
and the internet are becoming saturated with text-to-image produced imagery, and, artistically,
there are rapidly diminishing returns to the production of such images. Our aim with such
creative interpretations, and other more sophisticated generative projects we have planned, is
for generated images to be seen as artworks with an aura [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ], to be interpreted as part of a
thought provoking conversation, rather than merely to accurately portray a given prompt.
      </p>
    </sec>
    <sec id="sec-4">
      <title>4. Conclusions and Future Work</title>
      <p>
        With this position paper, we propose that neurosymbolic systems, especially those generating
novel content, could reason over knowledge bases of moral considerations which educate them
with higher-level lessons. We further suggest automatically extracting symbolic knowledge
from pre-trained models to aid in this. We are currently implementing prompt engineering
processes to employ in the context of the @artbhot [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ] twitter bot [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ]. Ultimately, we aim to
treat pre-trained neural models as fixed black-boxes, performing symbolic automated theory
formation [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ] to derive rule-based approximations of some of the semantic relationships they
capture, in order to better understand and control their usage.
      </p>
    </sec>
    <sec id="sec-5">
      <title>Acknowledgments</title>
      <p>We would like to thank Amy Smith for insightful comments on the web of meaning into which
artworks are situated. We would also like to thank Katherine Crowson and to the @nerdyrodent
developer for their work on the CLIP-VQGAN colab notebook and github repository. We would
also like to thank the anonymous reviewers for their insightful comments.</p>
      <sec id="sec-5-1">
        <title>Original “Truth”</title>
        <p>by Isaac Ganuza
“Fluid and
Threadbare Web”
“Wiry and
Torn Rope”
“Worn and
Forsaken Ruin”
“Wrathful and
Ancient Spirit”
“Harmonious and</p>
        <p>Imaginative
Transportation”
“Ofbeat and</p>
        <p>Grandiose
Machine”
“Energetic and</p>
        <p>Immense
Revolution”</p>
      </sec>
      <sec id="sec-5-2">
        <title>Original</title>
        <p>“Daniel-Henry
Kahnweiler” by
Pablo Picasso
“Triangular
Structure”
“Granular and
Dreary Rain”
“Quarrelsome
Confusion”
“Strident and
Jagged Shift”</p>
      </sec>
    </sec>
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