This became a difficult proposition with the Heisenberg Theorem of Uncertainty. The observer is necessarily bound up with the observed, the tools and filters affecting the conclusions of the experiment. If the scientist were to measure an electron, the tool would employ a photon. The photon would have to interact with the electron to have a result. Particles will interact, and waves will interfere.
All particles are also waves.
The result would be that the position, speed, or spin could be determined, but only one, nevermore. The spin of the particle is even harder to find. It is like seeing teddy bears in the clouds, it is never there until we have seen it. The spin will exist, but never known until the axis is chosen. Religion is the first theoretical science.