[Aquinasfan]

'Thinking' computers will likely not exist as long as we are using solely state electronics in their construction).

'Thinking computers' will never exist, because thought is an essentially non-material or spiritual phenomenon, and therefore cannot in principle be re-created materially.

Thought deals in universal ideas abstracted from sense experience.

MODERATE REALISM

This system reconciles the characteristics of external objects (particularity) with those of our intellectual representations (universality), and explains why science, though made up of abstract notions, is valid for the world of reality. To understand this it suffices to grasp the real meaning of abstraction. When the mind apprehends the essence of a thing (quod quid est; tò tí en eînai), the external object is perceived without the particular notes which attach to it in nature (esse in singularibus), and it is not yet marked with the attribute of generality which reflection will bestow on it (esse in intellectu). The abstract reality is apprehended with perfect indifference as regards both the individual state without and the universal state within: abstrahit ab utroque esse, secundum quam considerationem considerattur natura lapidis vel cujus cumque alterius, quantum ad ea tantum quæ per se competunt illi naturæ (St Tomas, "Quodlibeta", Q. i, a. 1). Now, what is thus conceived in the absolute state (absolute considerando) is nothing else than the reality incarnate in any give individual: in truth, the reality, represented in my concept of man, is in Socrates or in Plato. There is nothing in the abstract concept that is not applicable to every individual; if the abstract concept is inadequate, because it does not contain the singular notes of each being, it is none the less faithful, or at least its abstract character does not prevent it from corresponding faithfully to the objects existing in nature. As to the universal form of the concept, a moment's consideration shows that it is subsequent to the abstraction and is the fruit of reflection: "ratio speciei accidit naturæ humanæ". Whence it follows that the universality of the concept as such is the work purely of the intellect: "unde intellectus est qui facit universalitatem in rebus" (St. Thomas, "De ente et essentia," iv).

[JamesP81]

'Thinking computers' will never exist, because thought is an essentially non-material or spiritual phenomenon, and therefore cannot in principle be re-created materially.

Indeed. There is a group of computer scientists (can't remember what their theory is called, though) that have pretty much come to the same conclusion: that self-awareness is not a function of sufficiently sophisticated hardware, but is something that lies outside of science, or at least outside of known science. Basically, they believe the spark of self-awareness is a function of having a soul or something like it, something that cannot be replicated.

Of course, those of you who know me, know that I believe that we do have a soul given to us by the Most High God. A computer doesn't.

The only possibility I can see for 'thinking' computers, is to replace a computer's central processing unit and memory storage with a collection of neurons, essentially a cloned brain. I'm not sure if such a thing is even possible, and if it were, if it would work as expected (which I have serious doubts about). Furthermore, if someone did do it and it worked as expected, then I think that the resulting 'machine' would hardly qualify as a computer anymore.