Natural Order and Science

[Alex K]

But - What does "seeing a particle" mean other than that it was involved in the interaction with other particles (e.g. in you eye). That's what I am trying to get across here - the distinction between virtual and real particles seems not so well defined as to justify such a kneejerk distinction of their ontological status.

What is a particle but a name for a collection of phenomena with typical properties. What is a virtual particle but a name for a collection of phenomena with typical slightly not too different properties.

No, you didn't understand my post. Seeing means detected by not only your eyes, but also by any detector that will indicated it has been hit by those particles, either by a flash or a jump in voltage. Virtual particles are exchanged between two other particles, so those particles are NOT going to hit your eyes or any other detector. It's that simple.

What's the conceptual difference between particles in a detector (which is made from particles) and "two other particles"?