And Gate in Minecraft

Place two blocks next to each other (distance: one block). Install two redstone-lanes (both connected to a lever) which end in these blocks.
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Put two redstone-torches at the other side of these blocks and extract the signal of the torches by connecting the redstone-lanes.

Build another block right next to the extracted signal, and put a redstone torch at its back, too.
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Put the output-lane behind this torch.
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Explanation:
The output becomes positive, if all inputs are positive.