Spencer Heath Archive

Item 684

Random taping by Spencer MacCallum from conversation with Heath

May 1, 1956

Sir James Jeans, in one of his lectures, stated that the probability of another world like this being formed was as remote as the probability of two free-floating dust particles coming in contact within the great auditorium at Johns Hopkins University in which he was speaking.

He did not carry his thought far enough to realize that unless the cosmos is finite, the probability would be very high. If we consider an infinite number of instances such as he cited, then the probability of its happening once would be extremely high. In fact, in an infinite universe, it would be bound to happen an infinite number of times. Professor Jeans took the finite auditorium as an example of the whole universe. More properly, he should have included in his illustration an indefinite number of auditoriums, each having two dust particles floating in it, in which case the probability of their contact, however remote in the single instance, would be indefinitely multiplied in the indefinite number of instances supposed. In fact, unless he could assign limits to his universe, strict logic would compel him to recognize that the contact between the pairs of particles would be bound to happen not only once, or many times, but an infinite number of times.

That’s a pretty good argument for the assumption that the earth is not atypical or unique, and that whatever happens here must happen, in an infinite universe, an infinite number of times. This answers, in terms of probability, the question so often propounded, “Are there other worlds than ours?”