There’s been a flurry of articles in the UK press about a scientist’s suggestion that intelligent aliens would resemble us physically and psychologically. This means, I suppose, that we might have met a few without knowing it.

Alien Life Would Look Like Us

Probably not a clever creature….

This makes me consider robots (aliens of a kind, I suppose), and what it would take for us to accept that a robot is alive and intelligent, with an interior life, and therefore demanding of moral consideration. The Turing Test sets a very low bar in this respect since we demand more of life (unless we are extremely limited emotionally) than that an intelligent creature should type some textual responses from behind a screen.

As for intelligent alien life, I think the argument would go something like this:

The Implications of Language

• Intelligent life requires language and language goes with thought
• Language and thought can develop only in a community of creatures (where meanings and criteria for the use of words, especially mental words, can be implicitly agreed)
• Communities can only exist when language permits the ascription of thought by one individual to another, and this recognition of the other thereby involves compassion, the instinctive understanding (and feeling) of another’s thoughts, beliefs, pains, joys and feelings
• A moral, perhaps even legal, code based on such compassion would underpin any community of intelligent life
• Language and communities must evolve together
• A language can only exist if a life form possesses a face capable of highly complex (mostly involuntary) physical configurations, since language, thoughts, feelings and beliefs are ascribed and learned through facial expression (note that a blind person generally grows up in a community of sighted people)

Head, Brain, Eyes and Face – All Go Together

• Electromagnetic radiation (in our case the visual spectrum) offers the most powerful means of knowing things from a distance. Therefore aliens would have eyes.
• Eyes would be found near the highest point of an alien’s body so that the field of vision would be as large as possible
• An alien would possess at least two eyes (or some such similar mechanism) to enable the detection of distance
• Eyes would evolve in a face since the focus of the eyes is a vital component of understanding facial expressions which underpin the mental life and it wouldn’t make sense to look in two directions at once
• The eyes would evolve in proximity to the brain for rapid signal transmission
• They eyes would be heavily protected (sunk into something like a skull)
• The eyes would need to change their field of focus rapidly, therefore would need the ability to swivel. Protuberant eyes would be vulnerable, and it would be inefficient to swivel too much of the body, therefore intelligent creatures would have heads on necks, probably containing brains

Unlikely….

Ears Also Useful

• Language would probably use a medium other than electromagnetic radiation, because of the many advantages in being able to use eyes and ears separately, especially when the sun isn’t shining. You might imagine that a creature with more eyes than two would reserve at least one for language and communication, but eyes mean focus and that the interlocutor be in the field of vision, as well as that there should be light, so there would be advantages in using a separate medium such as distortions of the atmosphere (sound).

Hands are Special

• An intelligent creature would need precise control of as much of its environment as possible. Therefore it would have hands, probably at the end of highly mobile sticks (arms), since this would enable rapid movement near the body. Prehensility is another requirement (the opposing motion, for example, of thumb and first finger) since this enables grasping. The ability to write, draw and conduct orchestras might follow.

Mobility

• Wheels are unlikely, since, although they are efficient, they are less adaptable for jumping, reaching and stepping over things, than equipment such as legs. In any case roads and flat surfaces rarely occur in nature. Legs and/or fins of some kind would be the obvious choice, but I wonder if intelligent life could evolve underwater.

Unlikely to occur naturally…

What else might we assume? I am sure that many other aspects of biology and psychology might be derived from first principles, or am I being too anthropocentric in my thinking?

So, how different might an alien be? I think it’s logical to assume at least:

• Eyes, ears, face, brain, and at least one head
• Language, probably based on sound (in the atmosphere or in a liquid)
• Morality and community
• Arms, digits and prehensility, but no reason to stop at two and five of these
• At least two legs

We often wonder if we could create intelligent life. A lot depends on what you mean by intelligence, but setting the bar high, at the point where we must take moral account of such a creature, we would require the ability to use (even invent) language, to suffer convincingly, to express an inner life, to care, to learn and so on. I would think that the best materials for the manufacture of such a creature would probably not be metal and wire, but would be of biological origin – such as skin, muscle, etc. – so a convincing ‘robot’ would probably have to be human or look like an intelligent alien. Dr Frankenstein had the right idea.

Almost human…but made of the wrong stuff

HAL, the intelligent computer in Stanley Kubrick’s 2001 – A Space Odyssey is a robot/computer that’s almost human. HAL lacks skin and facial expression, (though he has a rather alarming red all-seeing ‘eye’), but his(or her?) beautifully modulated voice, and ability to plan, to deceive, even to ‘die’ in some distress at the end of the film, almost convince us that he is, or was, alive. That he could never have evolved independently of human life is irrelevant to the issue of whether he lives alongside human life. I think it’s his dying that tips the balance, since he evokes our reluctant compassion, but in reality this is the least plausible aspect of his behaviour, since it’s hard to see how or why his gradual regression to childhood makes any sense in a programmed device that did not grow up (as far as we know) in an organic way.

In fact, computers and robots are useful precisely because they do some things (simple, repetitive, number-crunching things) better than we do, and the more human they become – vulnerable, fallible, moral – the less useful they will be.