Demarcation Case

Demarcation

My goal this thesis is the examine one of the key debates in the philosophy of

science, the realism/anti-realism debate. Here I understand realism as 'scientific' realism,

that is, the thesis that the claims of a scientific theory concerning the reality of

unobservables are true, or at least can be counted on to be true in an advanced state of

scientific advance. Different philosophers enrich this debate, and in my thesis I will draw

a special attention to the anti-realist position called 'constructive empiricism' as

developed by the pre-eminent philosopher of science, Bas van Fraassen.

Constructive empiricists, according to van Fraassen, believe in a clear

demarcation line between observable entities and unobservable entities. As such, they

express doubt about the reliability of aided observation in scientific research; for them,

the epistemic value of aided/instrument-mediated observation is questionable. But a

realist's position is different in this regard. In an advanced stage of technological

development, they believe that we can rely on instruments to provide us with detailed

knowledge of unobservable, physical objects. That is, not only can we can acquire

reliable knowledge about the world through unaided observations but also by aided

observations. In the first chapter, my main task will be to try and show that the

constructive empiricists' demarcation line between observable and unobservable entities

is not acceptable. Human beings, I argue, can extend their power of observation by using

different instruments and, as a result, their power of observation is not constant -- it

develops with technological advance. This progress in technology, I submit, changes the

demarcation line between observable and unobservable entities. Moreover, I argue that

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the constructive empiricists' notion of naked eye observation is not itself without doubt;

sometimes naked eye observations deceive us. Such deceptive observations need