94 ANNUAL EEPORT SMITHSONIAN INSTITUTION, 1934 



a closed system detached from the perceiving mind; the perceiver 

 and perceived are interacting parts of a single sj'stem. The nature 

 depicted by the wave-picture in some way embraces our minds 

 as well as inanimate matter. Things still change solely as they 

 are compelled, but it no longer seems impossible that part of the 

 compulsion may originate in our own minds. 



Even the inadequate particle-picture told us something very simi- 

 lar in its own roundabout stammering way. At first it seemed to be 

 telling us of a nature distinct from our minds, which moved as di- 

 rected by throws of the dice, and then it transpired that the dice 

 were thrown by our own minds. Our minds enter into both pictures, 

 although in somewhat different capacities. In the particle-picture 

 the mind merely decides under what conventions the map is to be 

 drawn ; in the wave-picture it perceives and observes and draws the 

 map. We should notice, however, that the mind enters both pictures 

 only in its capacity as a receptacle — never as an emitter. 



The determinism which appears in the new physics is one of waves, 

 and so, in the last resort, of knowledge. Where we are not ourselves 

 concerned, we can say that event follows event; where we are 

 concerned, only that knowledge follows knowledge. And even this 

 knowledge is one only of probabilities and not of certainties ; it is at 

 best a smeared picture of the clear-cut reality which we believe to lie 

 beneath. And just because of this, it is impossible to decide whether 

 the determinism of the wave-picture originates in the underlying 

 reality or not — can our minds change what is happening in reality, 

 or can they only make it look different to us by changing our angle of 

 vision? We do not know, and as I do not see how we can ever find 

 out, my own opinion is that the problem of free-will will continue to 

 provide material for fruitless discussion until the end of eternity. 



The contribution of the new physics to this problem is not that it 

 has given a decision on a long-debated question, but that it has re- 

 opened a door which the old physics had seemed to slam and bolt. 

 We have an intuitive belief that we can choose our lunch from the 

 menu or abstain from housebreaking or murder; and that by our 

 own volition we can develop our freedom to choose. We may, of 

 course be wrong. The old physics seemed to tell us that we were, 

 and that our imagined freedom was all an illusion ; the new physics 

 tells us it may not be. 



The old physics showed us a universe which looked more like a 

 prison than a dwelling place. The new physics shows a building 

 which is certainly more spacious, although its interior doors may be 

 either open or locked — we cannot say. But we begin to suspect it 

 may give us room for such freedom as we have always believed we 

 possessed; it seems possible at least that in it we can mold events 



