Yes. Macbeth really does see the three Witches in the play. Banquo also sees them and speaks with them. Initially, Banquo questions the Witches about whether they are real or possibly a hallucination he and Macbeth both share, but throughout the rest of the play both men seem to accept the Witches as physical beings. Later in the play, the Witches appear with their Queen, Hecate, in a scene without any human characters. If Macbeth had been hallucinating the Witches, he would need to be onstage for them to be seen. He is not, which is more proof that in the world of this play, they are real. We can also contrast the treatment of the Witches to Banquo’s ghost. When Macbeth claims he sees the ghost, Lady Macbeth insists she doesn’t see anything, telling Macbeth “When all’s done/ You look but on a stool.” (3.4.) In the play, both Macbeth and his wife have hallucinations which they alone see, but the Witches are clearly visible to more than just Macbeth.