"You sense something," Windu said. "Something you haven't told anyone else about."
"So clever you are, Master Windu," Yoda said. "And so close to the truth. But think you not in the right direction, I say."
"What other direction is there, Master?" Windu asked. "Either you sense something or you sense nothing."
"Open your mind, Master Windu," Yoda said. "If sensed nothing is, something must it be."
"No," he said finally. "Nothing can never be something. They are opposites."
"So sure you are," Yoda said. "Reassuring, it is. Never so sure of myself am I."
"You think differently?" Windu said. It was starting to feel like a debate with Qui-Gon, and neither of them really enjoyed those.
"I think I sense nothing," Yoda said. "Presume anything after that, I do not."
"I trust your judgment, Master Yoda," he said at last. "I know if there is an answer, you will find it."
Yoda didn't respond. Instead, he closed his eyes and reached for the calm of the living Force flowing through him. After a few minutes, he felt Windu get up and leave him alone with his thoughts, which was his favorite place to be.
The light surrounded him, the dark a comfortable distance from the limits of his perception. And yet there was something; rather, there was nothing. And it eluded him completely.
Even though Yoda doesn't realize it, the nothingness he is sensing is Sidious's concealment. So I guess Yoda was the first Jedi to sense Sidious (if you want to call it that.)
and that was well before the dark side had taken control, when the Jedis ability to use the Force hadn't yet diminished, shows how powerful Sidious was even then
I know the Sheev inside you wants to make Palpatine a Force Wound. But what Yoda means is that he is undetectable.
__________________ RealistRacism: "Sheevites, much like the Banites, were meant to increase in power with each member. From Lightsnake to Gideon to Azronger, this was supposed to be the case. However, knowledge must've been lost in some kind of Gravid-like incident, as Az turned out to be a mid-tier debater with a sub-par track record, sh!itting all over Tempest's legacy. Sad."
the Dark Side of the force clouded his vision; after Maul killed Qui Gon who was the only chance of raising Anakin right and after Palps became leader of the free world id imagine that was the first big tip of the Force towards the Dark Side in the galaxy at large
Granted, Palpatine obtained more bureaucratic power, but I don't think TPM was some huge tipping point that massively shifted the galactic balance towards the dark side, and began hindering the Jedi's senses.
That shift only started happening in AotC. Hence Mace's line that the Jedi's ability to use the Force had been diminished, and Yoda's line that the shroud of the dark side had fallen.
Point being: Yoda was face-to-face with Palpatine for years prior to AotC, so why did he not sense the same nothing/absence from him?