Like other religions, buddhism can help reach a better state of mind. But there is no proof for the idea of repeated rebirths and karma.

There is plenty of proof, just not the type of proof likely to be accepted by people looking for a measurement from an external device, which precludes scientific proof until consciousness can be measured. Given that science cannot identify consciousness in live organisms at this time, you are going to have to wait a long time.

In general, there are three commonly accepted methods in Buddhist epistemology to know if something is true: perception, inference, and testimony. For the specific case of rebirth, common proofs use either perception, or inference.

- Perception: You train in states of concentration and use those to gain direct knowledge of past lives. Maybe some people would find this unconvincing even if they had the experience. Certainly not something likely to be accepted as scientific as Ian Stevenson's research has shown, even if the case presented was iron-clad.

- Inference: This uses Buddhist logic and an understanding of dependent origination. This specific argument comes from Dharmakīrti.

- Every moment of consciousness must have a substantial cause.

- Physical matter can serve as a cooperative condition for consciousness, but it cannot be consciousness's substantial cause, because matter and mind are fundamentally different in nature. Matter is extended, non-luminous, non-aware and consciousness is luminous and aware. If you are a scientific materialist, you will not accept this, but it must be noted that there is no scientific evidence of any kind for dead matter gaining awareness.

- Therefore, each moment of consciousness must arise from a preceding moment of consciousness of similar type.

- Then you trace this chain to the first moment of your present life. The chain must have been preceded by a moment of consciousness of similar type. The same logic applies to the last moment of your present life.

- Therefore, consciousness must be a stream that transcends physical birth and death.

Again, I am aware many people won't find this convincing, but to say that Buddhism does not attempt to prove rebirth and karma is not true.